Sori - suguta Torii/Koshi question-struggling

[jensen6865]

Hi all,

 

I am struggling with suguta and sori for period. The blade I am trying to figure out myself before I cheat and send it in has a very regular curve. If I take extremely precise measurements it is very slightly Koshi sori. Polished and suriage also involved.

I read the overall changes over time in the periods and watch the sift of sori as time goes on. Here is my problem. This blade only ends up fitting (in my feeble understanding) as yamashiro, but nothing fits with them except well before Late Muromachi. If it is "normal" Kamakura or Nambokucho it should be Koshi sori, but then I find that Torii Sori is actually sometimes called Kyo sori because Yamashiro wasn't always like the other schools. In such a case I have tryed to work somewhat backwards to try and figure. I realize that the low shinoji can be created by a lot of work over time and polishes, but even without it I am afraid I am stuck. Any thoughts or direction would be very much appreciated.

 

Thank you all, Dan

[paulb]

Dan

As your blade appears to be suriage and without any dimensions I think anyone would struggle to make an appraisal based on shape. As a first step try to imagne what the ubu blade may have looked like. If you think ytou can see koshi-sori then it is likely the ubu blade had this feature. Also look at the monuchi is there any evidence of saki sori or are the last few inches relatively straight?.

Once you identify these points and look at the current and likely original length it my give you a better idea of what you are looking at.

[jensen6865]

Thank you. I will give it a go!

 

Appreciate it, Dan

[Ken-Hawaii]

There are a number of other hints on your blade, Dan.

 

Take a close look at the machi area: where is it located, how are the mekugiana placed, & where does the hamon end? Lots of info there!

 

Ken

[b.hennick]

Dan Ken made a Kenshaku - a device used to measure sori. The device helps you to determine the location of the deepest sori and the magnitude of the sori. Without such a device the best you can do is to hold the sword with the tang vertical and at arm's length and then look at the whole blade to determine the deepest part. You can also lay the blade cutting edge up on a table with the machi at the end of the table (blade runs perpendicular to your seated position).and the point toward the center of the table.

[jensen6865]

Just when I think I am starting to have, "aha" moments I feel like the little kid in class again! Thanks guys. I will find out how to accurately locate deepest point of sori. Am I getting some of this correct? The machi used to be down about 8 cm more, the blade polish goes down to far below machi now. You can just see the hamon going almost down as far until it disappears into suriage? work on nakago? There is the old rust pit line across blade where used to end maybe.

But how the mekugiana are placed? Am I totally missing something about them? Obviously...! A hint maybe... I really want to figure this out, but WOW is there a lot of info....!

Am I safe in assuming that the overall length has been shortened if the nakago would only be about 4 1/2" long if it wasn't?

 

Thanks especially Ken and Barry, Dan